wgeoff

I think most migrants on Po Toi in autumn arrive from a north east direction, flying around the coastline probably from the Guangdong coast further east from Hong Kong, not via Hong Kong Island. This comes from visible migration confirmed by early overnight radar studies in the 70's and 80's. Some of them on Po Toi also come in from Dangan Island having arrived there the previous night from the same coastal migration route.

A few of them, like the Siskins, leave Po Toi heading in the direction of Hong Kong Island. Most head off towards Lamma or directly south west, missing Hong Kong altogether.

[ Last edited by wgeoff at 30/10/2010 18:12 ]

wgeoff

Yes, but you have to take other factors into account like suitable habitat for all types of migrants to feed and rest, and the multiplying effect of the Dangan Islands.

Sai Kung is too big to cover. Basalt, Town Island and Tung Lung Chau would be good (also in spring) but only if they have the right habitat. Shek O would be OK but it's not an island so birds can leave more easily. None of these will get the Dangan Island effect to the same extent as Po Toi. And then there's the question of getting there.

If I had the time and money, I'd go for Dangan Island itself (the north end) or a place called Gangkou on the coast of Guangdong east of Hong Kong (see inside cover of Birds of Hong Kong and South China). But then these aren't in Hong Kong.

wgeoff

It's quite late for Blue-and-white Flycatcher but not extreme.

Latest I have is two at Tai Po Kau on 10th December 2005, in 2005/6 Annual Report about to be published.